This invention relates to a seat for a motor vehicle and particularly to one of the type being removably fastened to the vehicle structure.
In some types of motor vehicles, and in particular multipurpose passenger vehicles (MPV's) there is a demand for passenger seats which can be installed to carry passengers or conveniently removed to provide a large compartment area for transporting articles. Irrespective of the design of the mounting system for a removable seat, it must have a high degree of structural integrity since extreme loads can be put on the mounting structure in the event of vehicle impact.
Various designs for removable seat mounting mechanisms are presently used in vehicles today. In order to provide the necessary structural integrity, the mounting system typically engages the floor pan of the vehicle below the front and rear edges of the seat, often pairs of front and rear seat mounts are provided at the four corners of the seat bottom. For these types of seats the forward laterally mounting points are merely hinge points with the rear mounts having a latching mechanism. Once the rear mounts are released, the seat can be pivoted forward and pulled from the forward seat mounts. The seat mounting points on the vehicle are typically comprised of bars or other structural features which are positioned below the floor pan surface in seat mounting sockets.
Since releasable mounting systems are required to have a high degree of structural integrity, some type of secure latching mechanism is required. In order to remove a seat having a pair of separate rear mounts the mechanisms are either designed to have separate release levers which must be simultaneously actuated by the user to remove the seat, or some type of remote control system is provided in which the pair of latches are both actuated through a single lever or release. Providing two separately actuated release mechanisms has the disadvantage that they must both be actuated simultaneously, which can be inconvenient to the user. If a single release mechanism is employed with a remote control system, a cable, torsion rod or another remote control element must be provided which adds to the complexity and costs of the seat mechanism.
Another shortcoming present in some existing seat mounting systems is their tendency to allow the seat to rattle against the seat mounts provisions, leading to undesirable noise and customer complaints.
In accordance with the present invention, a seat mounting system is provided which overcomes the previously mentioned shortcomings of prior art seat mounting mechanisms. In the seat of the present invention, two laterally separated rear latching mechanisms are provided. One of the latching mechanisms is a manually actuated release in which a latch plate is caused to engage and disengage a mounting bar attached to the vehicle floor pan. The latch plate is mounted to pivot about an eccentric cam such that it is cinched through spring tension to firmly clamp against the mounting bar, thereby reducing the possibility of rattling problems. Another releasable latch mechanism is provided which does not require a manual release since it is inertia sensitive, and will engage with a mounting bar in the event that the vehicle is subjected to a deceleration load above a certain level as might be expected in a vehicle impact. In the absence of the deceleration load, however, the inertia sensitive latch mechanism releases automatically when the manually actuated latch is released and the seat is pulled from its mounts. By providing a combination of a manually actuated and an inertia actuated latch, the requirement of dual manual release or remote actuation is eliminated. The design of the present invention also provides the significant advantage that an identical latch plate can be used for both the inertia sensitive latch and the manually actuated latch, thereby simplifying assembly and reducing the number of unique components which comprise the seat structure.
Additional benefits and advantages of the present invention will become apparent to those skilled in the art to which this invention relates from the subsequent description of the preferred embodiments and the appended claims, taken in conjunction with the accompanying drawings.